All WML and Lua code uploaded to the add-ons server must be licensed under the GNU General Public License (GPL). All Music, Sounds, and Art may instead be licensed under any Creative Commons (CC) license. Additional details can be found here on the wiki.

Add-ons must not use intellectual property from other sources, including but not limited to all commercial content and trademarks, unless that material is also under one of the licenses mentioned in #1.

Avoid gratuitous violence, sexuality, and mature themes in your content unless you give a word of warning about it which every player will see. This means more than stating it in the add-on's description, such as displaying a warning message when starting your add-on that all players must click through. By default, content is expected to stay roughly comparable to PG-13 or ESRB T.

Add-ons promoting excessively inflammatory political or ideological content may be removed from the server and possibly result in the removal of usage privileges. This applies both to content based on real world people and events as well as those occurring in a purely fictional setting.

Add-ons published must be offered in good faith for all members of the community to enjoy. Punitive measures up to and including bans may be applied for violations of this principle, which include, but are not limited to, employing mechanisms having the purpose or function of doing any of the following to one or more specific person(s):

Give them any gameplay advantage or disadvantage.

Prevent or hinder them from playing.

Insult or otherwise harass them.

All add-ons uploaded must actually be functional. This does not mean add-ons must be bug free or that they must be complete, but they cannot:

Prevent Wesnoth from functioning.

This does not include causing Wesnoth to freeze or crash, which should instead be reported as a bug on Wesnoth's Github page.

Cause errors elsewhere, when not playing the add-on's content.

Be effectively non-functional. For example: a campaign must be able to load its first scenario, and no add-on should create hundreds or more errors in Wesnoth's log.

Add-ons not adhering to the above rules should be reported to the Forum Moderators group, and may be deleted without warning. Any requests for the removal of add-ons infringing on copyright or trademark should be sent to the Forum Administrators group.

2014-06-13 — added point 9, addressing code that targets specific person(s)2017-08-20 — General update to the rules2017-09-08 — Added lost pbl instructions2017-10-01 — Added clarification to rules 7 and 82017-12-01 — Updated the copyright rules to point to the wiki2018-30-03 — Updated to mention data URIs2018-04-08 — Updated to remove rules regarding not using formatting and required fields, as these are enforced by Wesnoth.2018-21-12 — Removed rules about maximum upload size since it is enforced by the add-ons server, and removed the rule about working icons.